1. Field of the Invention
The present invention relates to apparatus employed to inject fluids into the flexible tube of an intravenous (I.V.) delivery set and more particularly relates to a novel injection site apparatus.
2. Description of the Prior Art
Several different types of injection site apparatus are presently commercially available. Prior art injection site apparatus require that the flexible tube of the intravenous set be cut or broken and that the injection site apparatus be inserted in series therewith. Connecting the severed ends or intermediate ends of the flexible tubes to the injection site apparatus presents several problems. When the flexible tube does not properly bond to the injection site housing leakage and/or contamination occurs. Prior art bonded connections have presented the possibility that an incomplete seal or weak seal will be made.
Most prior art injection site housings have spaces therein which entrap air. Further, the entrapped air can be administered to a patient when it passes out of the space in the injection site housing and into the flexible tube of the delivery set. The entrapped air in the prior art injection site apparatus could sometimes be removed with difficulty by inverting the housing, flushing and purging the air space in the injection site apparatus.
Some prior art injection site apparatus have no effective needle guides which permits the hypodermic needle to pierce the side of the housing or the flexible tube of the I.V. set or the connections between the housing and the flexible tube. It has been observed that such apparatus will permit the hypodermic needle to gouge into the housing so as to remove particles of the plastic housing which are flushed into the patient. The tip of the hypodermic needle can also become bent and unusable again. The hypodermic needle can become lodged into the side wall of the flexible tube so as to prevent flow of fluid. The hypodermic needle may be started into the side wall of a piercable closure in a manner which causes enough resistance to bend the hypodermic needle before it can enter into the fluid chamber of the injection site apparatus.
It would be desirable to eliminate the common problems of the prior art injection site apparatus in a simpler and cheaper structure.